在疑似深静脉血栓形成（DVT）的患者中，将D-dimer阈值根据年龄或临床前测试概率（CPTP）进行调整，与使用固定D-dimer阈值的标准方法相比，可以增加安全排除DVT的患者比例。目前这些诊断策略在癌症患者中的表现尚不确定。本研究旨在比较癌症门诊临床疑似DVT患者中年龄和CPTP调整的D-dimer方法的表现，并提出癌症特定的CPTP规则。 连续入选的活动癌症患者和临床疑似下肢DVT患者接受了Wells评分、D-dimer检测和全肢压缩超声检查的CPTP评估。正常超声检查的患者进行了为期3个月的随访，观察症状性静脉血栓栓塞的发生情况。 在239名患者中，48名（20.1％）确诊为DVT。年龄调整方法比标准方法具有更高的特异性和效率。与标准和年龄调整策略相比，CPTP调整策略的特异性和效率分别提高了35％和21％，但失败率、灵敏度和预测值在各种策略中都类似。根据Wells评分简化的CPTP评分减少了不必要的影像学检查，其准确性和效率类似，但失败率较高。在这个门诊癌症患者的前瞻性队列中，CPTP调整D-dimer策略具有最高的特异性和效率，相对于其他策略，可以安全地减少不必要的超声检查。需要进一步研究在这种情况下使用简化的临床预测规则的可能性。版权所有©2023 Elsevier Ltd。

In patients with suspected deep vein thrombosis (DVT), D-dimer thresholds adjusted to age or clinical pretest probability (CPTP) increase the proportion of patients in whom DVT can be safely excluded compared to a standard approach using a fixed D-dimer threshold. Performance of these diagnostic strategies among cancer patients is uncertain.To compare the performance of age- and CPTP-adjusted D-dimer approaches among cancer outpatients with clinically suspected DVT, and derive a cancer-specific CPTP rule.Consecutive ambulatory patients with active cancer and clinically suspected DVT of the lower extremity underwent CPTP assessment using the Wells rule, D-dimer testing, and whole-leg compression ultrasonography. Patients with normal ultrasonography were followed-up for 3 months for the occurrence of symptomatic venous thromboembolism.Upon referral, DVT was diagnosed in 48 of 239 (20.1 %) patients. The age-adjusted approach showed higher specificity and efficiency than the standard approach. Compared to the standard and age-adjusted strategies, the CPTP-adjusted approach had 35 % and 21 % higher specificity, and 34 % and 21 % higher efficiency, respectively. Failure rate, sensitivity, and predictive values were similar across strategies. A simplified CPTP score derived from the Wells rule reduced unnecessary imaging with similar accuracy and efficiency, but higher failure rate.In this prospective cohort of ambulatory cancer patients with clinically suspected DVT, the CPTP-adjusted D-dimer approach held the highest specificity and efficiency, potentially safely reducing unnecessary ultrasonography examinations compared to other approaches. Additional studies are warranted to evaluate the use of a simplified clinical prediction rule in this setting.Copyright © 2023. Published by Elsevier Ltd.